During the period, the president has instructed that the national flag should fly at half-mast at every station in the country from 1-7 May as a mark of respect and in observance of seven days of the national mourning.
Ramaphosa has visited the flood-stricken communities, assuring residents that all spheres of government would assist them in their rescue and recovery efforts.
“The president has also welcomed the wealth of material and social support extended to affected communities by various sectors of society,” the presidency said on Wednesday.
Some 70 people died in the disaster, a total of 1,469 people were displaced, and over 50 people were injured in the Durban area and other parts of the KwaZulu Natal Province.
“The president has expressed the profound appreciation of the government and people of South Africa for the messages of support received from governments around the world in relation to the recent floods,” the high office said.